This invention relates generally to improved apparatus for handling elongated paper roll tape of the type used with adding machines, calculators, and the like. More particularly, this invention relates to an improved yet relatively simple paper tape control unit for supplying paper tape to and for simultaneously rewinding paper tape discharged from an adding machine or calculator or the like.
Adding machines and calculators and other types of business machines are well-known of the type utilizing elongated strips of so-called paper tape. Typically, an elongated strip of paper tape is supplied in roll form and mounted on the adding machine or calculator, etc., by means of a rotatable spindle which permits the tape to be unrolled for supply to the business machine. The business machine commonly includes a roller platen unit or a similar mechanism for drawing the tape incrementally from the supply reel into association with a suitable printing head which applies numbers, letters, etc., into the paper tape. In most cases, the paper tape is permitted to discharge from the machine freely in an unrestrained manner which commonly results in elongated, tangled strips of paper tape which fall onto the floor in an unsightly manner.
A wide variety of paper tape control devices have been proposed for use with adding machines and calculators and the like, particularly to include a take-up reel onto which used paper tape is rewound simultaneously with unwinding of the tape from the supply reel. Many such paper tape control devices are integrated directly into the associated business machine, thereby providing a relatively large and complicated business machine construction, while other paper tape control devices have been designed as add-on components for association with a separate business machine. In general, however, these add-on components have also been relatively complex in construction and operation to include, for example, separate and relatively costly drive motors for winding the tape take-up reel. See, for example, U.S. Pat. Nos. 3,338,531 and 3,447,657. Other relatively simplified add-on control devices have attempted to drivingly interlink tape supply and take-up reels, for example, by use of friction roll-drive therebetween, but such devices have not adequately accounted for the inversely varying reel diameters as tape movement progresses, thereby frequently resulting in undesired or uncontrolled tape slack. Moreover, these devices have not facilitated rapid and simple review of used tape, nor have such devices provided a simple means for applying handwritten notes or edits to the used tape.
There exists, therefore, a significant need for an improved paper tape control device, particularly in the form of an add-on kit for use with existing calculators, adding machines and other business machines, wherein the control unit provides accurate, relatively slack-free paper tape motion control while permitting review of used tape and further accommodating the application of handwritten notes or edits to the used tape. The present invention fulfills all of these needs and provides further related advantages.